firewire: core: fix Model_ID in modalias
The modalias string of devices that represent units on a FireWire node
did not show Module_ID entries within unit directories. This was
because firewire-core searched only the root directory of the
configuration ROM for a Model_ID entry.
We now search first the root directory, then the unit directory. IOW
honor a unit directory's Model_ID if present, otherwise fall back to the
root directory's model ID (if present).
Furthermore, apply the same change to Vendor_ID. This had the same
issue but it was less apparent because most devices provide Vendor_ID
only in the root directory.
And finally, also use this strategy for the remaining two IDs in the
modalias, Specifier_ID and Version. It does not actually make sense to
look for them elsewhere than in the unit directory because they are
mandatory there. However, a uniform search order simplifies the
implementation and has no adverse affect in practice.
Side notes:
- The older counterpart of this, nodemgr.c of ieee1394, looked for
Vendor_ID first in the root directory, then in the unit directory,
and for Model_ID only in the unit directory.
- There is a single mainline driver which requires Vendor_ID and
Model_ID --- the firedtv driver. This one worked because FireDTVs
provide Vendor_ID in the root directory and Model_ID identically in
root directory and unit directory.
- Apart from firedtv, there are currently no drivers known to me
(including userspace drivers) that look at the Vendor_ID or Model_ID
of the modalias.
Reported-by: Maciej Żenczykowski <zenczykowski@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/firewire/core-device.c b/drivers/firewire/core-device.c
index 014cabd..c91d717 100644
--- a/drivers/firewire/core-device.c
+++ b/drivers/firewire/core-device.c
@@ -180,44 +180,32 @@
return 0;
}
+static void get_modalias_ids(const u32 *directory, int *id)
+{
+ struct fw_csr_iterator ci;
+ int key, value;
+
+ fw_csr_iterator_init(&ci, directory);
+ while (fw_csr_iterator_next(&ci, &key, &value)) {
+ switch (key) {
+ case CSR_VENDOR: id[0] = value; break;
+ case CSR_MODEL: id[1] = value; break;
+ case CSR_SPECIFIER_ID: id[2] = value; break;
+ case CSR_VERSION: id[3] = value; break;
+ }
+ }
+}
+
static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)
{
- struct fw_device *device = fw_parent_device(unit);
- struct fw_csr_iterator ci;
+ int id[] = {0, 0, 0, 0};
- int key, value;
- int vendor = 0;
- int model = 0;
- int specifier_id = 0;
- int version = 0;
-
- fw_csr_iterator_init(&ci, &device->config_rom[5]);
- while (fw_csr_iterator_next(&ci, &key, &value)) {
- switch (key) {
- case CSR_VENDOR:
- vendor = value;
- break;
- case CSR_MODEL:
- model = value;
- break;
- }
- }
-
- fw_csr_iterator_init(&ci, unit->directory);
- while (fw_csr_iterator_next(&ci, &key, &value)) {
- switch (key) {
- case CSR_SPECIFIER_ID:
- specifier_id = value;
- break;
- case CSR_VERSION:
- version = value;
- break;
- }
- }
+ get_modalias_ids(&fw_parent_device(unit)->config_rom[5], id);
+ get_modalias_ids(unit->directory, id);
return snprintf(buffer, buffer_size,
"ieee1394:ven%08Xmo%08Xsp%08Xver%08X",
- vendor, model, specifier_id, version);
+ id[0], id[1], id[2], id[3]);
}
static int fw_unit_uevent(struct device *dev, struct kobj_uevent_env *env)